You can set up a Group for your family or friends and share your Premium Service subscription.
To do so, first, subscribe to Premium Service. (iSharing > Menu > Premium service)
Then, create a group for your family or friends and invite all members that you want to share your Premium Service subscription with.
Please note that your group members can use Premium Service, but it will be limited to the specific group. They need to be viewing your specific group through the group selector. Then, they will be able to use Premium Service features.